"But seeing they could not See; hearing they could not Hear"
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"From its chamber comes the whirlwind, and cold from the scattering winds." - Job 37:9.

"The wind blows to the south and turns to the north; round and round it goes, ever returning on its course".

Wednesday, June 13, 2012

Thunderstorms Likely - Some Extra "Potent"

Osceola County east of Kissimmee on Tuesday. Elevated "shelf cloud" resultant from a Dry and Stable Sea breeze well inland , with no (zero) Convective Available Potential Energy with the sea breeze

TODAY: Potentially 'interesting' day in store for much of the state, with only the region south of Lake Okeechobee not really playing in.  The East Coast Sea breeze has begun as far north as the Cape Kennedy Area at least at last observation. Exactly how far inland it will progress will be a key factor today regarding where the strongest activity will occur. It would seem most likely that the further north one progresses the less inland (if any) westward progression the boundary will make.  There are indications that the east coast sea breeze will especially active today though already, based on the trends of some parameters last seen prior to this post that would support stronger than usual thunderstorms.

A trough of low pressure resides to the far end of the state, but that will not be as much of a factor as much as the mid-upper level trough stretched diagonally from ENE to WSW across far North Central.  High clouds associated with a mini-jet stream streak continue to proliferate South Florida, with East Central over Brevard at this time experiencing the greatest upper level divergence associated with the highest Convective Available "potential" Energy, Instability, across the state just inland and to the WSW as far south as the north side of Lake Okeechobee. This is one reason to watch Dead East Central: Brevard, Southern Volusia, Seminole, Eastern Orange and Osceola Counties over toward  Indian River and St. Lucie Counties (late). Further north toward North Volusia and Flagler, the boundary itself seems will be a greater player due to its closer proximity as well as an upper level vorticity max that has moved little so far since sunrise. This 'vort max' extends across all of East Central however, with the energy "advecting" across the eastern 1/2 of the region. Air temperatures aloft and forecast soundings as well as forecasts of those temperatures would justify at least considering frequent lightning, wind gusts around 45mph and pea sized hail. Any storm  resulting from the perfect collision of the sea breeze and outflow from another storm in collapse phase could result in a funnel cloud , especially along the east coast  sea breeze, where ever that may be located  later this afternoon. Steering of storms, in general, is west to east at 15mph. 

The strongest of storms it would seem will be those that latch on to the east coast sea breeze boundary and work SSE-SE ward against the late afternoon sea breeze (if that in fact will occur at all) if that were to occur. Currently the wind is 'quite easterly' in Canaveral and SE further south, but that wind should start to become much more southerly Central locations from Ft. Pierce and north later today due to the Coriollis Effect .  This will increase low level helicities  (spiraling horizontal winds) being pulled into higher instability located just away from the coast. Thus, the most potent storms in regard to hail potential and just maybe a funnel are noted in red below. 

In reality, the red zone could be 1/2 that size, but given the early time of the afternoon, and the fact that the sea breeze is in place which none of the models were showing at the time of this posting    was to even be in place, this throws a vital wrench in whatever the time delayed forecast models are showing. 

Given the track record though..the red and purple zones are contenders for some 'potent to extra potent' lightning producing storms and small, nuisance hail. That is not to say that a storm or two will not exhibit pulse Severe  or Near Severe characteristics. Chances are, any storm that can produce such winds will also be one that can produce the near severe hail size.   Other storms could occur across far North Florida, but due to the greater focus toward Central, have not mentioned in today's post.  Area to keep a second eye might very well end up being from near Vero toward Ft Pierce.  Air aloft here is much drier, so whatever can go up in that area in earnest would need to be watch, the question is..can anything go up there in earnest to start with. Some areas could also receive a storm or rain shower more than once.  The other, last but not least thing to consider is brief, localized in those areas most prone to it,  flooding of road ways in pour drainage areas due to brief but heavy rainfall.

THURSDAY: Another variation of today, only different. This does not say a whole lot, other than many of the same areas could get wet again, to include South Florida.  We will be in-between boundaries, as the northern one will hesitate a bit as low pressure forms offshore the Carolinas. The main factor to watch by then will be the boundary at 2000 ft, since surface boundaries appear to get absorbed/absolved away during the day.

 That 'upper' boundary  just above the surface will work down the state into South Central by Thursday evening some it appears perhaps the strongest activity will be from Cape Canaveral and South on Thursday. The boundary then clears much if not all of the state by Friday mid-day, as Northeast winds, some quite gusty from New Smyrna and north work in. Coastal showers possible on Friday and Saturday and into Sunday, especially north of West Palm Beach, but in general it appears they will be isolated, perhaps scattered from time to time, but decreasing in likelihood later on Sunday and into Monday as winds become more easterly and decrease.

BEYOND INTO MID WEEK: Easterlies continue, light. Eyes are on the extreme Western Caribbean toward the Yucatan Bay. The GFS and Euro came into close agreement as of this morning for the first time, taking 'something' toward Brownsville in days to come. On the other hand, it was only just the run before that the GFS brought a large tropical storm northward toward Mississippi, then curving it east ward toward the Panhandle or Big Bend area. AND, to make matters worse, the run before that showed no tropical storm development at all. To cut to the chase, given that if or when anything forms is beyond the time frame of model consistency (obviously) as well as reliability, there is little point in focusing on this issue until there is something to see. Invariably, guidance will be bouncing all over the place until that time, and even still and yet, once something does exist (if it does at all)..we then go into Phase II of uncertainties. Thus, as an added bonus at this point, we are only adding uncertainty atop more uncertainty.  Much of the discrepancy, should one ask, seems to be concerning the strength of high pressure over the Atlantic that will be in place once those aforementioned easterlies are in place (as a result of   high pressure over the Atlantic):  where it will be located,where it will move, and its strength and persistence. 

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